package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.binary.BaseNCodecOutputStream;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

//检验用户是否完成登录
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    private static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
//        1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求：{}", requestURI);
//        定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/common/**",
                "/backend/**",
                "/front/**",
                "/user/sendMsg",
                "/user/login"
        };
//        2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
//        3、如果不需要处理，则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);
//放行
            filterChain.doFilter(request, response);
            return;
        }
//        4、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("员工已经登录,用户id为",request.getSession().getAttribute("employee"));
            long id = Thread.currentThread().getId();
            log.info("线程id为：{}",id);
            Long empID= (Long) request.getSession().getAttribute("employee");
//            调用BaseContext的setCurrentId方法将当前登录用户ID存入ThreadLocal。
            BaseContext.setCurrentId(empID);
            filterChain.doFilter(request,response);
            return;
        }
        //4-2、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已经登录,用户id为",request.getSession().getAttribute("user"));
//            将id存入session中
            long userId=(Long)request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
        }
//        5、如果未登录则返回未登录结果
        log.info("用户未登录");
        R<Object> notlogin = R.error("NOTLOGIN");
        response.getWriter().write(JSON.toJSONString(notlogin));
        return;
    }
//    路径匹配，检查本次请求是否放行
    public boolean check (String[] urls, String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
